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Maine court finds part of referendum blocking transmission line to Massachusetts unconstitutional

Now, it’s up to a lower court judge to decide whether the project can go ahead.

Maine's highest court on Tuesday breathed new life into a $1 billion transmission line that aims to serve as a conduit for Canadian hydroelectric energy, finding part of a statewide vote rebuking the project unconstitutional and sending it back to a lower court to decide.Robert F. Bukaty/Associated Press

An embattled transmission corridor considered critical to Massachusetts’ climate effort was given new life Tuesday, after a ruling by Maine’s Supreme Judicial Court seemingly brought it back from the dead.

The project, which would bring hydroelectric energy from Quebec, through the wilds of western Maine and into Massachusetts, is a key piece of how Massachusetts plans to convert its energy grid from fossil fuels to clean energy.

But a vote in Maine last year to block the project left the transmission line on life support, all but dooming a major piece of Massachusetts’ plan to rapidly clean its power grid and likely setting the state’s climate efforts back by years.


The ruling Tuesday is far from a full green light for the project. The judges found that part of the Nov. 2021 referendum was unconstitutional, sending the case back to a lower court to decide its future. It will be up to that court to decide whether enough of the project had been completed prior to the vote that stopping it now would be unconstitutional under Maine law.

But many clean energy advocates were heartened.

“Like everyone, we were waiting with bated breath to see what the court would say, and it wasn’t clear which direction they would go,” said Daniel Sosland, president of the clean energy advocacy group the Acadia Center.

The $1 billion transmission line, known as the New England Clean Energy Connect, represents markedly different things to different groups.

To the Mainers who opposed it, it is a destructive 145-mile wound through Maine’s wilderness, intended to help Massachusetts reach its clean energy goal at the expense of its northern neighbor.

To those who supported it—in Maine, Massachusetts, and beyond—it’s a crucial part of how Massachusetts will slash emissions and comply with a state law mandating net-zero emissions by 2050, as well as a bellwether for the many other large-scale transmission projects that must be constructed if the country is to successfully transition off of fossil fuels.


“The bigger picture here is that it would have massive climate impact to bring a reliable flow of clean electricity to the largest urban region in New England,” said Joe Curtatone, president of the Northeast Clean Energy Council, a regional clean tech organization. “Mostly, we hope lessons are learned from it so that we can avoid similar rancor with future projects.”

The five members of the court found it was unconstitutional to retroactively apply the referendum because the project had already completed substantial construction based on the permits it had already received and sent it back to a lower court for further proceedings.

In a statement, Avangrid called the decision a victory for clean energy. “It is time to move away from the status quo fossil fuel companies who will undoubtedly continue their fight to maintain a stranglehold on the New England energy market,” the company said.

In court filings, Avangrid and Central Maine Power say they have invested nearly $450 million dollars on the project, and that a significant portion of the work was already done at the time of the vote. That includes cutting 124 miles of right-of-way—over 80 percent of the total—along the corridor, more than 120 structures that have already been built, and more. Not to mention, the lengthy permitting process.

The project’s future depends on whether a lower court finds that, at the time of the statewide referendum vote, the transmission line was far enough along that it had established what’s known as vested rights.


Opponents to the transmission line argue that Central Maine Power, a subsidiary of Avangrid, sped up its timeline to complete as much work as possible despite knowing that the referendum was coming. “We think it’s very well documented that CMP really rushed to build this, despite the fact that this referendum was ongoing, despite the fact that they knew they were going to lose this referendum,” said Adam Cote, an attorney with Drummond Woodsum who is representing opponents to the transmission line.

Massachusetts cannot reach its mandate of net-zero emissions by 2050 without greening the electricity grid, and while wind and solar are expected to make up a significant portion of that, Canadian hydro is “an essential element,” according to the state’s roadmap for reaching that goal.

In the roadmap, experts laid out various scenarios for how Massachusetts will rapidly cut its emissions. All of them called for between 2.7GW and 4.8GW of expanded transmission between Massachusetts and Quebec—but it has been unclear how the state would achieve it.

An earlier plan to bring the energy via New Hampshire was rejected over opposition to the project’s aesthetic and potential environmental impacts. In Maine, the opposition stemmed from similar worries, as well as concerns that Mainers did not stand to benefit from the project and opposition from indigenous groups in the state.


“Today’s decision is difficult to interpret but what is clear is that there will be further review of these issues by lower courts,” said Colin Durrant, media relations and advocacy communications director for the Natural Resources Council of Maine, which opposes the transmission line. “It is unclear when that review will take place or how long it will take.”

The New England Clean Energy Connect is the result of a deal among Hydro-Quebec, the state of Massachusetts, and Central Maine Power. It aims to bring 1,200 megawatts of hydropower from Quebec to New England’s power grid. Prior to Maine’s vote last year, it was expected to start delivering energy to Massachusetts by December 2023.

The project had the backing of the governors in Maine and Massachusetts, US Energy Secretary Jennifer Granholm, and a smattering of environment and clean energy groups. In the lead-up to the referendum vote, record-breaking political spending poured into the state, as outside experts called the project a bellwether for the large climate projects that will be necessary across the country as the economy shifts off fossil fuels and increasingly electrifies.

“Conflicts such as that caused by the Maine referendum severely challenge our ability as a society to make progress on reducing emissions,” said Michael Walsh, an independent decarbonization consultant who helped the state develop its 2050 roadmap. “We need to develop better participatory frameworks way to handle such conflicts at both the local and regional scales.”

Sabrina Shankman can be reached at Follow her @shankman.